Electrophotographic image forming apparatuses such as laser printers are generally configured to form an image on a recording medium such as a sheet of paper or a transparency (hereinafter referred to as a recording sheet) by transferring a developing agent or toner. However, some of the toner to be supplied may remain on a photosensitive drum or a conveyor belt, and become waste.
If printing or image formation is performed with waste toner remaining on the conveyor belt, the waste toner adhering to the conveyor belt may be unintentionally transferred onto a backside of a recording sheet causing an undesired image to be formed on the backside of the recording sheet.
To prevent recording sheets from being printed with undesired images, some image forming apparatuses are provided with a waste toner container. The waste toner container is configured to collect and accommodate or hold waste toner.
To increase capacity of the waste toner container, the volume of the waste toner container should be increased. However, if the volume of the waste toner container increases by increasing its height dimension, the image forming apparatus will increase in height.
If the volume of the waste toner container increases in the length dimension, a current pump for conveying waste toner can experience difficulty in conveying the waste toner to the back of the waste toner container. Much waste toner may accumulate at the entrance of the waste toner container, making it difficult for the container to hold a sufficient amount of waste toner if the volume of the container increases.
The capability of conveying can be improved by increasing the size of the pump for conveying waste toner. However, this may result in increasing the size of the image forming apparatus and the pump.